CoMP (Coordinated Multipoint, coordinated multipoint) is one of key technologies of LTE-A (Long Term Evolution-Advanced, long term evolution-advanced), and is used to extend coverage of a high data rate, increase average throughput of a system, and especially improve performance of edge users.
CoMP is a type of cooperative transmission and reception technology. A base station is connected to at least one access point, and an access point may include one or more antennas. Multiple users may be served by one or more access points located at a same base station or different base stations. CoMP transmission/reception technologies may be mainly classified into two categories: (1) joint scheduling: sectors belonging to a same collaboration set exchange information, and perform joint scheduling, so as to obtain an interference coordination gain; (2) joint reception: a serving sector and multiple collaborative sectors simultaneously receive a signal sent from a same user, which is equivalent to that the number of antennas at the receive end is increased, and an MIMO (Multiple-Input Multiple-Out-put, multiple-input multiple-output) receiver is used to improve demodulation performance.
For a certain user, CoMP gains of the user vary with different sectors selected to perform collaboration. In order to increase the CoMP gain of the user, sectors for collaboration need to be selected. An existing CoMP selection scheme is that: it is assumed that a base station corresponds to three sectors, namely Cell 0, Cell 1, and Cell 2, and a serving sector, where a UE (User Equipment, user equipment) is located, is the Cell 0, therefore possibly formed CoMP collaboration sets corresponding to the UE are: {Cell 0}, {Cell 0, Cell 1}, {Cell 0, Cell 2}, and {Cell 0, Cell 1, Cell 2}; the base station separately calculates a signal to interference plus noise ratio (Signal to Interference plus Noise Ratio, SINR for short) of data that is received by the four collaboration sets and equalized, and selects a collaboration set corresponding to a largest SINR as a final CoMP collaboration set.
However, in an actual application scenario, energy of a data signal received by a collaboration set except a serving sector is normally lower than that of the serving sector. Therefore, in actual channel estimation, a measurement error of the SINR after equalization is performed is large, leading to a large error in selecting a collaboration set according to the SINR, and a selection result is inaccurate, thereby resulting in a negative gain.